Unregulated antibiotic sales in pharmacies and online are fueling the rise of deadly “superbug” bacteria as the world sits on the cusp of an “antibiotic apocalypse,” according to a UK government-commissioned report.

Antibiotics can only be obtained by a doctor’s prescription in the UK, but it is relatively commonplace in many low- and middle-income countries for the drugs to be bought over the counter.

The report published on Friday urges governments, regulators and online firms to clamp down on unlicensed sales of antibiotics.

It comes amid global alarm about the discovery in China of a gene that makes bacteria resistant to even the strongest available antibiotic, prompting some scientists to warn the world is on the cusp of a ‘post-antibiotic era.’

In the government-commissioned report, former Goldman Sachs chief economist Jim O’Neill said the global threat is exacerbated by patients self-medicating with drugs from online pharmacies.

“Even in those countries where it’s next to impossible to buy antibiotics over-the-counter in a shop, it’s still often the case that an unscrupulous online pharmacy is just a few clicks away,” he said in a statement.

“These internet drug stores could be based anywhere in the world, so it’s vital that regulators – along with the industry, customs organizations and internet companies – work together to crack down.”

Professor Timothy Walsh of the University of Cardiff’s Institute of Infection & Immunity told the BBC the world is on the cusp of the “post-antibiotic era.”

“All the key players are now in place to make the post-antibiotic world a reality,” he said.

“If MCR-1 becomes global, which is a case of when not if, and the gene aligns itself with other antibiotic resistance genes, which is inevitable, then we will have very likely reached the start of the post-antibiotic era.

“At that point if a patient is seriously ill, say with E. coli, then there is virtually nothing you can do,” he added.